Learn Russian: Взвесить все недостатки — это довольно разумно. - Weighing all the disadvantages is quite reasonable.

When the subject of a sentence is an infinitive (взвесить) and the predicate is an adverb or a noun, Russian often uses a dash to link them, functioning like the verb 'is' in English. The word это is frequently added right after the dash to emphasize the connection: 'To weigh all the disadvantages — this is quite reasonable.'

Why use the perfective infinitive взвесить instead of the imperfective взвешивать here?

We use the perfective взвесить because the sentence focuses on the result of a single, completed action. You want to successfully finish evaluating the disadvantages before making a decision. If we used взвешивать, it would imply the continuous or repeated process of weighing them, which sounds less like practical advice and more like a general philosophical statement.

This lesson focuses on words like стоит and следует, but they aren't in this sentence. How does this structure express a similar idea?

Using an infinitive followed by это and an evaluation word (like разумно, важно, or хорошо) is another very common way to give impersonal advice or express value. While стоит взвесить means 'it is worth weighing,' взвесить — это разумно gives the exact same type of recommendation by stating that the action itself is a reasonable thing to do.

Does взвесить literally mean 'to weigh' physically, or is it only used metaphorically like this?