As Artie sat at Ting's workbench, filing the teeth of a gear, still thinking about the drawing of the cube his mentor had made, another memory made its way into his mind. It was something that his younger sister, Alicia, had said sometime last week when she was talking to her best friend Maris.

Artie had been fishing in the creek behind Ol' Stoney when he overheard Alicia and Maris talking about their lessons from earlier in the day. Maris' mother had made use of a Nature walk to introduce the idea that they lived in a sea of ceaseless change, even going so far as to state that one could "never step in the same river twice."

Of course the two girls were still fixated on what must have seemed like a very odd statement to each of them.

"Alright Maris", Alicia said, "I'm going to step in the river, and then step in it again."

"I don't think that's what my Mom meant", said Maris, "well-aware that her mother's statements usually had several layers of meaning."

Artie was tasked with watching them for the next hour or so, which was just fine with him since it allowed him to sit outside and spend time by the water. His younger sister saw the smirk on his face and immediately made a comment.

"What's so funny?", queried Alicia in somewhat of an indignant manner.

"Oh, nothing", replied Artie, miserably failing at a half-hearted attempt to conceal his smile.

"Well, big brother", stated Alicia, "It's pretty obvious that I can step in the same river twice. Despite what Maris' mother claimed."

Artie couldn't help but laugh at his sister's outburst. For someone so young, she spoke more like an adult than a child and absilutely hated an insinuations that she might miss something or could possibly be wrong about something.

"I don't think that's what she meant", said Artie, biting the side of his cheek to hide his inner urge to smile.

"Then what did she mean?", pressed Alicia, thoroughly unimpressed with her brother's response.

"I think that Auntie Nina meant that the river is continually moving, like the river of time itself", said Artie, "and that the water is always refreshing itself, no matter where you step."

"Well, duh", replied Alicia, "That's just common sense."

Artie, like most big brothers, couldn't resist the opportunity to attempt to one-up his sister and immediately made another comment.

"It's a common theme with Heraclitus," stated Artie, "like when he said that 'the only thing constant is change'."

"Oh", responded Alicia, "I thought he said that 'change is the only constant.'"

"He did", said a female voice with a distinctively older timbre.

"Auntie Nina!" exclaimed Alicia, "Artie and I were just talking about Heraclitus - you know, the fire philosopher."

"Indeed" said Nina, "Why don't you share your question with your brother?"

"The one about the shape of time?" inquired Alicia.

"Exactly", replied Nina.

"Alright big brother", said Alicia, "When Heraclitus said that 'change is the only constant', did he mean that the sape of time is always the same?"

"The shape of time?" sputtered Artie.

"Yes", replied Alicia, even more matter-of-factly than before.

"I don't know", whispered Artie, "I've never really thought about it."

"He doesn't know either", piped in Maris, "See, I told you it's a silly question."

"No it isn't!", yelled Alicia, aiming her outburst at her best friend's ear.

"Alright, it's time to go", said Nina, as she corralled the two girls away from the river.

Artie sat by the river and pondered his sister's question, unsure exactly what to make of it. He had never thought of time as having a particular shape, let alone a constant one. While Ting didn't seem too surprised when Artie told him about his sister's question, he didn't rush to supply an answer to Artie either.

These were the thoughts that cycled through Artie's mind as he used a jeweler's file to smooth the burrs off the tiny brass gear. All in all, it was an incredibly tedious process. Each time he finished cleaning off two or three teeth, Artie had to unclamp the jaws of the vice, rotate the gear, and gently reclamp the gear.

"The shape of time.", Artie thought to himself before smoothing the edge of another tooth, "What an interesting question..."

In between his finishing work, Artie continued to contemplate his sister's question — never realizing that he was quite literally staring at the very answer to his question.