Understanding beginningless I often see the word beginning-less in Buddhist readings and on this site but how do I try to understand this concept being the ignorant human being I am?


Is it just a metaphorical way to describe a very long time?
Is it like the saying which came first: the egg or the chicken in which the answer ‘doesn’t matter’ since they’re both here in the now?
Or is it what we experience is an illusion created from our ignorance therefore there is no real beginning.


Scientists say our universe is roughly about 13.8 billion years old so there is probably a beginning? I am not accepting they are correct but not denying the fact either. 

I feel like when people use the word beginning-less, they are using it as an excuse to explain something that is “unexplainable” because how can something be beginning-less?Is it futile to try to grasp this concept? Or if this concept is understandable what can I do to see this?
I have not read the term "beginningless" in the Pali suttas, which refers to a "beginningless beginning", similar to chicken vs egg. 

The Pali suttas use the phrase: "without discoverable beginning", which means a first occasion cannot be discerned. 


  Bhikkhus, this is said: ‘A first point of ignorance, bhikkhus, is not seen such that before this there was no ignorance and afterward it
  came into being.’ AN 10.61
  
  
  
  Bhikkhus, this saṃsara is without discoverable beginning. A first point is not discerned of beings roaming and wandering on hindered by
  ignorance and fettered by craving. SN 22.99
  
  


In other words, "ignorance", for example, is the present 1st cause for the manifestation of suffering. Here, Buddhism does not attempt to answer the question: "What came before or what causes ignorance?". This is why the term: "without knowable beginning" is not analogous to the chicken vs egg scenario. The Pali suttas are saying: "It is not knowable when ignorance 1st began or what caused it however ignorance exists in the present moment that causes suffering". 

Therefore, Buddhism does not affirm or deny the 'physical universe' (which is not the meaning of 'samsara') may have had a beginning, such as the Big Bang (despite the illogicalness of the Big Bang theory).