57 Facts About Leonard Hofstadter

Penny is Leonard Hofstadter's next-door neighbor and main love interest, and the teasing of romance between the two of them is a major force driving the series.

Leonard Hofstadter is one of four characters to appear in every episode of the series, along with Sheldon Cooper, Howard Wolowitz, and Rajesh Koothrappali.

At night Leonard Hofstadter wears a white t-shirt, a maroon robe and white socks.

Leonard Hofstadter is instantly captivated by Penny, and from the beginning sets out to date her.

In early episodes, Leonard Hofstadter is reluctant to let Penny know about his recreational activities, as he does not want her to see him as a geek.

Leonard Hofstadter is musically inclined, as he can play the cello.

Early in the series, Leonard Hofstadter tried to get rid of his collectables to impress Penny with his maturity.

Nevertheless, Leonard Hofstadter often finds himself explaining Sheldon's behavior or serving as a mediator between him and other people in many situations.

For instance, when Penny and Sheldon engaged in a fierce dispute, Leonard Hofstadter gave her Sheldon's mother's phone number so she would call her son and scold him for his behavior, thus ending the fight.

Leonard Hofstadter explains to Penny that he moved in despite the difficulty of living with Sheldon because the rent was so reasonable.

Leonard Hofstadter is prone to jealousy, often feeling insecure and defensive whenever Penny interacts with other men, and on one occasion trying to frighten off a British college student she was doing a project with, because Penny commented positively on his accent.

Leonard Hofstadter wears eyeglasses because of myopia and cannot see clearly without them.

All of the members of Leonard Hofstadter's family are accomplished scientists, except for his younger brother Michael, who is a tenured law professor at Harvard University.

Leonard Hofstadter has a personality almost identical to Sheldon's, including strict speech patterns, lack of social conventions, and attention to detail, and she is principally responsible for Leonard's difficult childhood.

Leonard Hofstadter is upset with the fact that she tells Sheldon more than she tells him, but later decides it's okay.

Leonard Hofstadter revealed to Penny that he built a "hugging machine" when he was young in order to compensate for the lack of affection from his mother.

Leonard Hofstadter further stated that his father used to borrow it.

Beverly belittles Leonard Hofstadter by pointing out that his brother and sister are more successful in their respective fields than he is.

Leonard Hofstadter's brother, Michael, is a Harvard law professor and is engaged to the youngest appellate court judge in New Jersey history, and his older sister, whose name is unknown, is a cutting-edge medical researcher working with gibbons to cure diabetes.

However, Beverly admits in season 11 that Leonard Hofstadter married the best out of his siblings, after she develops a genuine friendship with Penny.

Leonard dislikes his memories of Christmas, not just because he never celebrated it, but because instead of gifts the Hofstadter kids had to turn in papers to "Santa" which were graded the next day.

Leonard Hofstadter finally confronts his mother, telling her of the many ways she has hurt him.

Leonard Hofstadter is embarrassed by his middle name and its humorous connotations, and rarely mentions it.

Leonard Hofstadter has Alzheimer's disease and apparently "had an episode" during her visit, which resulted in her stripping off her clothes and carving the turkey.

Leonard Hofstadter mentioned an Aunt Nancy, apparently a "crazy cat lady" who had 25 cats, died, and was eaten by them.

Leonard Hofstadter has an IQ of 173, and was 24 years old when he received his PhD from Princeton University.

Leonard Hofstadter received a dissertation of the year award for his doctoral paper on experimental particle physics.

Leonard Hofstadter has been established to have been a child prodigy, and a gifted scientist with an impressive knowledge of theoretical physics.

In season 8, Leonard Hofstadter has a revelation about Superfluid Vacuum and with Sheldon's help was able to come up with a paper that impresses the scientific community including Stephen Hawking.

Leonard Hofstadter became interested in Penny almost immediately after seeing her for the first time.

Leonard Hofstadter then tells Sheldon that she lied to Leonard about graduating from community college.

The next day, Leonard Hofstadter gives Penny brochures for local colleges.

Penny gets offended, thinking Leonard Hofstadter is calling her stupid, so they stop seeing each other.

Besides Penny, Leonard Hofstadter has been involved with only a few other women.

Leonard Hofstadter's friends recalled on many occasions that they were together for only 27 days, after which Joyce, later revealed to be a spy, defected to North Korea.

Leslie breaks up with Leonard Hofstadter by saying him believing in String theory is a "deal breaker".

Leonard Hofstadter met Stephanie when Howard picked her up at a bar by telling her she could drive a car on Mars.

Leonard Hofstadter finally goes to Howard's house to tell him what is happening, but right as he goes to say it, Stephanie calls Howard and tells him first.

However, the relationship ended after eight months, after Leonard Hofstadter told Penny he loved her and took umbrage at her inability to reciprocate, which led to friction that was exploited by guest star Wil Wheaton who appeared as a fictionalized version of himself, who observed and exacerbated it in order to break them up in the middle of a bowling match Wheaton's team was having against Leonard Hofstadter, Penny, Sheldon, Howard and Raj.

Shortly after his breakup with Penny, in "The Plimpton Stimulation", Leonard Hofstadter has a one-night stand with Dr Elizabeth Plimpton, a physicist he admires, when Sheldon invited her to stay in their apartment for a brief visit.

Leonard Hofstadter arrives home the next morning, whereupon Penny recognizes his "walk of shame" and Sheldon thinks Leonard Hofstadter has a future in becoming a gigolo to rich ladies in exchange for donations.

Raj strongly opposes this, and Penny is secretly uncomfortable with Leonard Hofstadter dating someone else, eventually breaking down and crying while talking with her friend Amy Farrah Fowler.

Subsequently, Priya pressures Leonard Hofstadter into ending his friendship with Penny, which he attempts with extreme reluctance.

Leonard Hofstadter later goes to a wedding with Amy, and after Leonard Hofstadter spends most of the time acting depressed and moping.

Later, despite feeling that he and Priya were in love and might get married, Leonard Hofstadter finds himself attracted to a comic book artist named Alice.

Leonard Hofstadter then decides to confess his behavior to Priya via Skype, but he is shocked to learn that Priya has betrayed him, sleeping with her former boyfriend; Priya defends that they both slipped up a little, but Leonard Hofstadter corrects her saying that he slipped a little, while she slipped a lot, bringing the conversation to a strained end.

Leonard Hofstadter decides that since they are no longer dating, he can be honest and does not have to pay for everything or do whatever Penny wants.

Leonard Hofstadter admits that she is very happy with him, but she admits to commitment issues and the thought of being married forever really "freaks" her out.

Leonard Hofstadter then tells her that when she is ready to get married, she can propose to him.

Leonard Hofstadter happily accepts, but during the journey, after Penny expresses happiness that they will get married while knowing everything about each other, Leonard Hofstadter confesses to having shared a drunken kiss with another woman while on the boat in Europe, though he adds that the woman started it and he rejected her.

Penny becomes hurt by the revelation, and even though she claims to forgive Leonard Hofstadter, there is clearly tension between them, leaving the season ending in a cliffhanger as to whether or not they will go through with the wedding.

Leonard Hofstadter barely remembers the incident and quickly grows bored with Leonard's ramblings, taking a sarcastic and dismissive tone toward him.

From that meeting, Leonard Hofstadter comes to terms with his insecurities and he and Penny are able to become more comfortable in dealing with their mutual fears about their relationship.

Leonard Hofstadter seriously tries to move into Penny's apartment though Sheldon has serious objections and makes them compromise to spend multiple nights a week in Leonard Hofstadter's old room.

Leonard Hofstadter is touched by the video and realizes that Penny genuinely loves him and not just out of desperation or pity.

Later Penny's old boyfriend Zack Johnson and his new wife want Leonard Hofstadter to be a surrogate father to their kid since Zack is infertile.

Penny reluctantly agrees to let Leonard Hofstadter do it until Leonard Hofstadter finally changes his mind not wanting a child in the world that he can't raise.