In the end (en definitiva, al fin y al cabo)

Summarizing with en definitiva

Use en definitiva ("ultimately" or "in short") to cut through the noise and boil an argument down to its core truth.

We question existence, but, ultimately, there are no answers.
Cuestionamos la existencia, pero, en definitiva, no hay respuestas.
Ultimately, it is very easy to judge a mistake.
En definitiva, es muy fácil juzgar un error.

Reaching conclusions with al fin y al cabo

Use al fin y al cabo ("after all" or "in the end") to justify a statement or point out what remains true when everything else is stripped away.

After all, the meaning of morality is different for everyone.
Al fin y al cabo, el significado de la moral es distinto para todos.
After all, freedom has consequences.
Al fin y al cabo, la libertad tiene consecuencias.

Punctuation

These phrases often appear at the beginning or end of a clause. When inserted in the middle of a sentence, they are set off by commas.

As long as you follow the rule, morality is, ultimately, simple.
Mientras sigas la regla, la moral es, en definitiva, simple.
You act as if you could judge me, but, after all, we are the same.
Actúas como si pudieras juzgarme, pero, al fin y al cabo, somos iguales.