Frost send Thomas a poem in 1915 called Two Roads, soon to be rechristened The Road Not Taken and often called The Road Less Travelled. It finishes:
I shall be telling this with a sigh
Somewhere ages and ages hence:
Two roads diverged in a wood, and I –
I took the one less traveled by,
And that has made all the difference.
Since its composition The Road Not Taken has often been read as an affirmation of individual choice and being different, choosing a different road to the rest of us. But it was never intended to be read in this way by Frost. Thomas read it as a criticism of his indecision and reacted angrily. He did join the army and was killed in 1917.
If you read the poem carefully there are clues that it’s not as straightforward as you think. The two paths, he wrote, had been worn "really about the same", and "equally lay / In leaves no step had trodden black", showing the reader that neither road was more or less travelled, and that the choices may in some sense be equal. Anyway no matter which road you take, it will make all the difference.
If you read the poem to a large group of people and ask them which road would they choose, I guarantee than over 90 per cent will choose the less travelled one. Hmmm! How can it be less travelled so? This is the same as that feeling everyone has that they are different to the rest of us, the common herd.
I’m choosing the road more travelled on the basis that there will be very little traffic on it!
Good review of the book with a discussion of this poem here.