When to use the article "el" with infinitives in Spanish?

Question

What is the difference between, for example, "el comer" and just "comer" when used as a noun? The case I'm thinking of would use a gerund in English. For example,

El comer chuches antes de cenar no es bueno.

vs.

Comer chuches antes de cenar no es bueno.

vs. the English

Eating sweets before supper isn't good.

In the Spanish examples, what difference in meaning, if any, is there when using the article "el?" This specific example is just for discussion, but I'd like the answer to address the use general.

Answer 1

On this website you can see all the possible uses of infinitives in Spanish. It's written in Spanish, but it basically says that:

1. In Spanish, infinitives can play the role of a substantive.
2. While playing the role of a substantive, infinitives can act as the subject of a sentence.
3. While acting as the subject of a sentence, infinitives may or may not be preceded by the article "el".

Note that if the infinitive is not playing the role of the subject, it must not be preceded by the article.

I'm not sure if the explanation on that site is absolutely academic, but what I'm positive about is that there's no difference of meaning in your examples and the same happens in other sentences where the infinitive is the subject of the sentence...

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Also note, as said in the previous site, that there are some infinitives in Spanish that have been converted into substantives, so that they can always be preceded by the article, such as:

• El saber
• El poder
• El amanecer
• El anochecer

Answer 2

To add to MikO's nice answer:

• In the example, both forms are correct, the second one (without article) is slightly more natural and frequent.

• When the infinitive is used as noun, but not as the subject, the article is always omitted: "Me gusta comer".

• Further, even when the noun is used as subject, but it is placed after the verb, the article is almost always omitted: "No es bueno comer chuches antes de cenar" is the correct way.

• Considering the above, a non-native speaker would like to play it safe and adopt the rule of omitting the article always. However, be aware of the last part of MikO's answer: some words like "saber" in a phrase like "El saber no ocupa lugar" is not really a verb acting as a noun (the action of knowing, conceived as a thing) but a plain noun (a thing -the knowledge-, not the action), hence the article is mandatory.