And if one cannot come close, how did it happen - ואי לא סמיך היכי משכחת לה
Summary:
תוספות explained why the question is not on אביי (only on רבא), the answer of ר"פ, the questions on ר"פ, the answer of רבינא and the question on רבינא.
It can be inferred that Rabi Yosee maintains that the one damaged needs to distance, etc. - מכלל דסבר רבי יוסי על הניזק להרחיק וכולי
Summary:
The מקשן who asked 'ואי לא סמיך היכי משכחת לה', was aware that the רבנן maintain that the דבורים לא מזקי לחרדל, while the מקשן who asked 'מכלל דסבר ר"י וכו was not aware. Therefore in the בשלמא the argument between ר"י ורבנן was whether the דבורים are מזיק, but not as 'תוס explained it according to רש"י that their argument is whether סמיכה בהיתר makes you a ניזק but not a מזיק.
And does Rabi Yosee maintain that the damager is required, etc. - וסבר רבי יוסי על המזיק כולי
Summary:
רבינא is retracting what was previously assumed, and concludes that according to רבא it is only by a בור that it is אסור לסמוך even if there is no other בור, but in all other cases since there is no ניזק, the סומך cannot be considered a מזיק. The מחלוקת between ר"י ורבנן is where the דבורים were סומך.
