Confusion in Lesson 7.3

"Como no conocer a nadie" - this expression is used in the written dialogue but in the spoken lesson it seems this expression is used interchangeably with "no conozco a nadie". When is the infinitive used rather than the first person? Thanks.

It seems to me that "Como no conocer a nadie" means "Not knowing anybody" which is a general statement without a subject,therefore the use of the infinitive is O/K. "No conozco a nadie" on the other hand means " I don't know anybody", whereby the subject is "I" and the verb conocer is therefore conjugated to conozco. In a sentence where there is a subject, the first verb would be conjugated accordingly to match the subject and you can then use further verbs in the same sentence in their infinitive form. The first verb used defines the subject, it is not required to further define the subject with repeating the conjugation in subsequent verbs. I hope I have this right. :)