What Is Past?

What is past?
Past, upto the first letter, is prime

Prime, in math, is a set
And that set is P
1^st prime is 2
2^nd prime is 3
And then so on
P is, thus, {2, 3,…}

What!
P is prime
And that prime is past
And that past was empty

Yes!
Empty is ϕ
ϕ, therefore, is P

OK!
Wait a minute!
Present – what about that?
The first letter of which, too, is P

Well done friend!
You got it!
The present is in no way different than past

Here is how they go
Was was is
Is is was
And
Were were are
Are are were
And
Am am am
And
Shall is shell
Will is well
And then so on