A/N: First TBBT fic! An epic friend of mine has recently gotten me hooked...and rightly so, because I'm uncomfortably similar to Sheldon sometimes. Just ask the few friends I have ;-)

Hope you enjoy!

"There. It's simple. And after all that quantum physics, it's time for a joke." Sheldon paused dramatically. "Don't trust atoms. They make up everything."

Leonard laughed appreciatively. "That's a good one, Sheldon."

"I know."

Penny didn't laugh. Her face contorted in a frown as she stared at the board, which was a cacophony of letters, numbers, and symbols. "I just…I don't get it. Any of it. I mean, I got a B in high-school biology! How can science be this ridiculously un…ununderstandable for me?"

Sheldon surveyed her with patient skepticism. "I believe the word you are looking for is 'incomprehensible.' Or perhaps you would prefer—"

Leonard shot him a glance and put a friendly hand on Penny's shoulder. "It's Ok, it's a lot to take in…and Sheldon was talking fast. Plus, Penny, you're smarter than you think."

Sheldon scoffed. "How is it possible to be smarter than one thinks? Is not thought the means by which intelligence is expressed? Penny's thoughts on her own intelligence most likely delineate exactly the extent of her intellect's capacity."

"That's stupid," Penny snapped, folding her arms.

"Sheldon." Leonard pressed his temples. "Most people think they're not as capable as they are."

"If she underestimated her abilities, that is indeed unfortunate. But it's alright now."

"It's alright?" Penny's eyebrows lifted in hopeful confusion.

Sheldon smiled pityingly. "Yes. Because any chance of reversing your damaging self-esteem issues likely deteriorated years ago."

She glowered at him. "Yay."

"Grover Cleveland was so rotund he got stuck in a bathtub," Sheldon supplied comfortingly.

"Sheldon! Who the hell is that, and what the hell does that have to do with anything?"

Sheldon looked surprised. "Why, he was also president of the United States. He's proof that our impediments don't have to destroy our chance for success."

Penny chewed on her lip thoughtfully. "So…you're saying I can go on to great things and overcome my…I don't know…stupidity?"

"Oh, no, I wouldn't say overcome. He was still fat." He paused. "You can't overcome your lack of intellectual capacity, but at least you're not fat." He cocked his head appraisingly. "Yet."

Penny's eyes narrowed dangerously.

"Sheldon—" Leonard made a frantic chopping motion in the air.

Sheldon continued, unperturbed. "He also was the only president to serve two non-consecutive terms in office."

Penny flicked her hair from her shoulders. "And what makes you think I would care about that?"

Sheldon shrugged. "He, like you, had something disconnected."

An hour later…

"She punched me." Sheldon sounded as aggrieved as he had the first seventy-two times he had said it.

Leonard sighed as he passed him a new ice pack. "Yes, Sheldon. You made her angry."

"I only explained her troubles to her."

"Sheldon…you know those insurmountable impediments you brought up?"

"Yes?" Sheldon looked wary.

"You have one too."

"Excuse me?" Sheldon was affronted. "And what might it possibly be?"

"Some of us call it common sense."