I would often walk on the tips of my toes when I was a small child when I was stimming and/or acting silly, and I normally walked toe to heel. I trained myself to walk heel to toe after my parents and teachers told me it was bad for me. Interestingly, after I went through an illness that left me unable to walk for a while I had to re-learn to walk, and I naturally wanted to walk toe to heel again. Sometimes, I still walk that way because it feels better to me.
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While Mr. Kim... has fallen prey to the inexplicable need for human contact, let me step in and assure you that my research will go on uninterrupted, and that social relationships will continue to baffle and repulse me.
- Dr. Sheldon Cooper (TBBT)