Did you wonder why it's "lo mismo" and not "el mismo" or "la misma" in our examples above? The answer is that "lo" is the neuter article in Spanish and it is used to stand in for an abstract idea, concept, category or quality--in other words, something that's not a concrete object or person. One way to translate it is as "thing" -- but sometimes there's no easy translation.
Here are some more phrases that take "lo" before an adjective:
lo bueno = "the good part, what's good"
lo fácil = "the easy part, what's easy"
lo important es que... = "the important thing is that..."
lo mío = "(that which is) mine"
lo nuestro = "(that which is) ours"
lo más = "the most" -- as in LoMásTv, of course!
Let's look at the refrain once more (with "lo" as our focus):
No es lo mismo una sospecha que saberlo de verdad
A suspicion isn't the same [thing] as knowing it for sure
No es saberlo de verdad lo mismo que una sospecha
Knowing it for sure isn't the same [thing] as a suspicion
Captions 7-8, Circo - La sospechaPlay Caption
Now, you've noted that "lo" is standing in for something unknown in this song -- something that's neither masculine nor feminine per se. When "lo" appears before an adjective or adverb, it's easy to recognize as neuter. But, to complicate matters, "lo" can also be a masculine direct object -- as in, "Lo vi" ("I saw him"). The only way to straighten out whether "lo" is a masculine or neuter object in a sentence is via the context.
In our Circo song lyrics, the second "lo" (-- "saberlo") also stands in for something undefined. As the direct object of a verb, lo works in a similar way in these common phrases:
Lo siento = "Sorry" (or, literally, "I feel it")
No lo sabía = "I didn't know [it]"
No quiero saberlo = "I don't want to know [it]"
For more on the neuter, see
ThoughtCo.com > Spanish language > The neuter gender in Spanish
When we premiered the spacy music video Bienvenido by Sizu Yantra several months ago, we received this letter:
If someone had asked me to translate "if you find the world sickly" I might have come up with "si el mundo tú encuentras enfermizo"... could someone explain why the "lo" is in there? --DonJorge, San Mateo, CA
Si al mundo lo encuentras enfermizo, delirante y brutal...
If you find the world sickly, delirious and brutal...
Caption 2, SiZu Yantra - BienvenidoPlay Caption
When lo is not busy working as a neuter article (e.g. lo importante, "the important thing/what's important"), or as an "undefined" neuter direct object (e.g. No puedo creerlo, "I can't believe it"), lo can also be found serving duty as the masculine singular direct object pronoun, just as la does as the feminine singular direct object pronoun.
¿Dónde encontraste el perro?
Lo encontré en la calle.
Where did you find the dog?
I found it on the street.
¿Desde cuándo has querido a María?
Siempre la he querido.
Since when have you loved Maria?
I have always loved her.
¿Quien rompió la mesa?
Juan la rompío.
Who broke the table?
Juan broke it.
As you can see, when we mention the direct object by name (e.g., el perro), it comes after the verb. When we replace it, the direct object pronoun (such as lo, or la) comes before the verb.
However, it is permissible in Spanish to mention your direct object by name AND put it before the verb, but if you do this you must include both the object and its pronoun. When we do this we provide more emphasis to the direct object, as Sizu Yantra emphasizes "el mundo" in the example above.
Al perro lo encontré en la calle.
I found the dog in the street.
La mesa la rompió Juan.
Juan broke the table.
Now's a good time to go back and take another listen to Bienvenido by Sizu Yantra! (it's in the "Music Videos" section).